The author ts extremely grateful to all the contributors for
high standard of the new chapters, and hopes that you,
reader, will enjoy going through these pages as much as
challenge because the region is packed
with small, important structures.
These structures are associated with
the proximal ends of the respiratory
and gastrointestinal systems,, the
cranial nerves, and the organs of
special sense, all of which are found
within the region. Dissection of the
head and neck provides a special
problem in that peripheral structures
must be dissected long before their
parent structure can be identified. I
fficrior gefidlon ol \Egus nffv€
The iuqular foramen transmits:
- Glosso-pharyngeal, vagus and accessory nerves (lX, X, XI).
A tumor invading iugular foramen mav lead to:
- Loss of taste sensation from posterior Ts of tongue.
- Increased intra-cranial pressure.
- Paralysis of muscles of soft palate.
It is the soft tissue covering the
t. Skin: rich in hair follicles &
2. Elonnective tissue (dense & fatty):
o When injecting local anesthetic,
the tip of the needle should be
3. Aponeurosis: flat membrane.
4. Eoose areolar connective tissue
(the dangerous area of the scalp):
allowing free mobility of the 1't 3
layers on the underlying A"gporomrrvm
. Loosely attached to the bones, but firmly attached to suture lines.
. Continuous with the outer layer of dura at the foramen magnum.
gu0edo( saoitlal sinut Arachmid
Ail'achFdid rBatet . &.fiarsfuidsFftB
This is the loose areolar C.T. layer.
- which connect scalp veins to the dural sinuses.
attached to the skull (at superior nuchal line).
- Frontalis is not attached to the skull.
- The muscles of the scalp are innervated by the facial nerve.
Lymphatic Drainage Of The Scalp: *
- To the superficial circle of LNs around lower part of skull ) deep LNs around
Blood & sensorv nerve supplv of the scalo:
Branches of ophthalmic a. of the
G, fupertorthrr ftc$ftal arlery
) unit to form faciat vein at the mediat orbitat marsin
Points of Suroical Importance:
E The 1st three lavers of the scalp are intimatelv united & should be consjdered as
. Comprise the superficial 3 layers.
o They are turned downwards & not upwards (nerves & vesse/s enter the
. Subcutaneous hematoma is small, tense & painful.
. Sub-aponeurotic collection of blood: may extend anteriorly to the
eyelids forming black eye & posteriorly to superior nuchal line
(attach ment of occipito-frontalis).
. Sub-periosteal collection of blood:
- ls limited by attachment of the periosteum to the suture lines.
- Feels like depressed fracture due to fibrin deposition at its
tr The scalp has very rich blood supplv. this explains:
. Wounds of scalp bleed profusely. Bleeding can be stopped by compressing the
scalp over the underlying skull bone.
. Wounds heal well; minimal debridement is required & wound infection is
There is no subcutaneous fat in scalp ) no lipoma.
Plentiful sebaceous qlands make the scalp one of the most common sites for
Emissary veins do not have valves and open in the loose areolar tissue;
therefore, infection can be transmitted from the scalp to the cranial cavity. The layer of
loose areolar tissue is known as the dangerous area of the scalp.
Metastatic spread of maliqnant lesions in front of the auricle is to the parotid and
cervical groups of lymph nodes. The posterior part of the scalp is drained to the
occipital and posterior auricular groups of lymph nodes.
tr Anastomosis exists at the medial anqle of the eve. between the facial branch of
the external carotid arterv and the cutaneous branch of the internal carotid
arterv. During old age, if the internal carotid artery undergoes atherosclerotic changes,
the intracranial structures can receive blood from the connection of the facial artery to
the dorsal nasal branch of the ophthalmic artery.
Each side of the neck is divided into anterior & posterior triangles by the sternomastoid
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